Fish welfare: the crossroads of science, ethics and comparative veterinary medicine

Dr Matt Landos BVSc(HonsI) MACVS (Aquatic Animal Health)

<sup>Principal, Future Fisheries Veterinary Service
PO Box 364 Lennox Head NSW 2478

matty.landos@gmail.com</sup>

• Abstract
• Full paper
• Discussion
• Acknowledgements
• References
  
  

Abstract

The global focus on aquatic animal welfare has been increasing in every area of human interaction with these animals. In 2007, by way of review and update, an entire edition of the Diseases of Aquatic Organisms was dedicated to papers from key international authors on aquatic animal welfare. The key points raised by these authors will be briefly presented. This will include comparative neurophysiology, evolutionary anatomy and behavioural studies. The growing body of evidence for sentience in teleost fish creates some ethical and legislative quandaries, given the standard of interactions that humans have with these animals.

Full paper

Rose (2007), Anthropomorphism and mental welfare of fishes

This paper states that in order to understand the nature and welfare needs of fishes, we need to use means other than anthropomorphism. Rose suggests this should necessarily be based on the natural behaviour and life history of the fish species. Anthropomorphism draws on the innate human psychological trait whereby we interpret things as if we were in their shoes. Rose argues that we have enough difficulty understanding one another, hence empathising with fishes is virtually impossible for humans. Consciousness is said to be a recent evolutionary phenomenon possessed only by humans; and since fish did not evolve from humans, they must be considered psychologically different from humans. Rose goes further to say that speculation about happiness, boredom and other anthropomorphic conjectures are unfounded and are detrimental to our objective of attaining welfare for fishes. Does a fish feel sorrow after having eaten another? Does a fish feel love during breeding season? Does an Orca feel delight in killing a Minke whale? Fishes live in a "fish eat fish world". Policy should not be shaped on whether or not fishes have conscious awareness, nor should it be to make people feel better about being humane. Rose supports using the model of critical anthropomorphism and it involves using objective reasoning such as the knowledge of a fish's species-typical biology and measurable environmental requirements such as reproduction, stress response, growth, disease resistance and maladaptive behaviour.

Iwama (2007), The welfare of fish

The author states that we do not need validation on whether fish share our experiences to care for their well-being. This conclusion was reached because the author asserts that all experimentation to date is inconclusive and provides data that is ambiguous. We have an ethical responsibility towards respecting the life and well-being of all animals in our direct care or influence by minimising stress as guided by behavioural, physiological and cellular indicators.

Bergh (2007), The dual myths of the healthy wild fish and the unhealthy farmed fish

The author is pro-fish farming and his paper addresses the common misconceptions of wild fish being "healthier" than farmed fish. The reason for this is likely due to the paucity of data on the health of wild fish. He explains that the contrary is true since the advent of prophylaxis, better management practices and therapeutic control measures.

Volpato et al (2007), Insights into the concept of fish welfare

The authors concede that empirical science is unable to prove, or to disprove, that fish are sentient organisms and that physiological patterns for assessing welfare is wrought with difficulties. This paper hopes to influence the direction of future research by proposing a combined ethical-scientific methodology referred to as the "fish-preference approach". Variables such as temperature, salinity, pH, space, photoperiod, light intensity and colour, feeding times and quantity can direct guidelines for codes of practice. However, experimental design and interpretation of results from such experiments must be treated with caution as "preferences" are shaped by availability of choice, opportunities and by intrinsic factors such as phylogeny, biological rhythms, ecology and grouping. Preference testing not only provides useful information to protect fish from suffering, but it also provides for access to 'comfort states'.

Turnbull et al (2007), Safeguarding the many guises of farmed fish welfare

The authors believe little progress has been made on fish welfare because there is no consensus on the issue. People are debating on different questions and having different definitions of fish welfare. Fish welfare has been put into 3 categories based on feelings, function and rights. Feelings is concerned with prevention of pain and suffering; function deals with good health with normal biological function and the absence of disease; and rights requires that an animal is allowed to express its natural behaviour and live in an environment to which it is adapted. This paper is positive that fish welfare is achievable even in the absence of consensus provided that emotion is set aside and that the information is presented in an effective manner taking into
account cultural and religious differences. Through discussion, it is hopeful it will lead to a better understanding of all aspects of fish welfare.

Lund et al (2007), Expanding the moral circle: farmed fish as objects of moral concern

The authors track the origin of welfare principles and animal ethics within moral philosophy, and follow through with presentation of science mostly related to sentience. The authors note the international trend for the inclusion of fish, decapods and cephalopods in welfare legislation. The authors note that current science cannot provide an unambiguous answer on the presence or absence of fish sentience, and suggest it is likely to be present, hence fish welfare should be considered on ethical grounds. This is in alignment with the view of Singer (1990) who insists that the presence of sentience ought to decide whether a moral concern should be valid for a species. The authors believe sentience is present based on arguments of common neuroanatomy and neurophysiology, and the analogy of convergent mental evolution. Further support for sentience is the evidence of behaviours indicative of advanced cognitive skills, including spatial memory, social intelligence, learning and memory in response to noxious stimuli. It is the authors’ opinion that fish deserve the benefit of the doubt and note that ultimately it is an ethical judgement based on science, and not a definitive scientific decision.

Bekoff (2007) Aquatic animals, cognitive ethology, and ethics: Questions about sentience and other troubling issues that lurk in turbid water

In a self-professed pro-animal dissertation Bekoff argues that respect and moral consideration should be automatic for all animal taxa, as all are valuable, based on ethical obligation. This is based on arguments rooted in non-speciesism and the evolutionary conservation of pain pathways, and by inference the sentience to experience pain. The paper suggests a greater emphasis on cognitive ethnology (the study of animal minds) is required to understand the subjective, emotional, empathic and moral lives of aquatic animals. The author also suggests that in the absence of absolute knowledge it would be prudent to utilise the precautionary principle and do no harm, cause no pain and suffering. He points out the debate is often divided between animals rights campaigners who take the position that human benefits derived from aquatic animals are irrelevant in the debate to determine the appropriate treatment for them. This contrasts the animal welfarist’s utilitarian approach to the issue, where humans are the beneficiary. Bekoff argues that biocentric anthropomorphism should be utilised to assist a determination on the emotional state of animals.

Braithwaite and Boulcott (2007): Pain perception, aversion and fear in fish

The authors accept the research that puts forward compelling evidence that teleost fish have similar pain processing systems to terrestrial vertebrates. The paper examines the scientific research which investigates whether behavioural and physiological changes observed to noxious stimuli, are indicative of higher order cognitive processes and thereby indicate whether a subjective assessment of pain or suffering can be made. The reviewers believed that more research into motivational affective states are required to demonstrate that fish have behavioural and physiological attributes which characterise conscious cognition or affected states. Whilst the authors conclude that “fish potentially have the capacity for long-term suffering” they recognise the need for further research as a priority.

Broom (2007): Cognitive ability and sentience: Which aquatic animals should be protected?

The author details the evidence for sentience in some species of fish, decapods and cephalopods, citing perceptual ability, pain and adrenal systems, emotional responses, long and short-term memory, complex cognition, individual differences, deception, tool use and social learning. He suggests the case for protecting these animals is compelling. Historical views of which species are considered sentient continues to change in developed nations. Broom identifies many of the welfare issues in the fish-farming industry including stocking density, feeding methods, catching and killing methods, environmental quality enrichment, disease and parasitism, handling, grading, transport and predation.

Mather and Anderson (2007): Ethics and invertebrates: A cephalopod perspective

The authors observe that invertebrates are not highly valued as a species, hence have not been seen to be deserving of conservation or welfare protection, with humans appearing indifferent to animals that are unlike us. The authors review the invertebrate case through 3 philosophical viewpoints: Contractarian/Kantian, Utilitarian and Rights-based. The later two arguments require an assessment of pain, suffering and pleasure to dictate how we should behave in relation to these animals. A range of invertebrates from mussels to cephalopods certainly possess the neurological and endocrinological systems in common with higher order taxa to perceive noxious stimuli, and elicit physiological and behavioural responses to aversive stimuli. Octopuses had been found to exhibit a range of reactions to a standard stimuli, suggesting individuality was a feature. Learning capacity has also been identified in cuttlefish with early life enrichment altering adult behaviour and in octopus in consequence of actions experiments. Whilst it is arguable that this confers any central cognitive capacity, the authors go on to outline more work demonstrating adaptive learning. Evidence for self-awareness and self-consciousness in octopus is presented. Authors believe irrespective of the viewpoint taken, cephalopods warrant an evaluation of our ethical position toward them. Some research labs have taken this on and have ethical care and management measures in place for cephalopods. Enrichment of environments is a focus.

Discussion

The progress in understanding the neuroanatomy, neurophysiology and behavioural science of aquatic animals continues to provide a flow of information which challenges existing human behaviour with aquatic animals. The sentiment of public towards aquatic creatures is changing, albeit more slowly, than in all other food and pet animal industries. Some companies are already exploiting this sentiment for a marketing advantage in seafood.

It is indeed fortunate that there is a strong correlation between good welfare and improved productivity in the aquaculture industry. This is already driving improvements in production and harvest techniques in the aquaculture industry. The market forces driving humane production are also assisting industries to develop codes of conduct and improve their fish welfare.

The situation is more vexed in the ornamental aquarium, recreational and commercial fishing sectors. In these significant industries, the current techniques lead to poor welfare outcomes for the aquatic animals concerned. From live baiting, to sport fishing, to crushing and asphyxiating tonnes of fish in the back of a commercial trawl net- these practices will be increasingly challenged by the volume of evidence supporting the assertion that aquatic animals do indeed demand the ethical respect of humans, and legislative welfare protection.

The application of the Prevention of Cruelty to Animals Act varies greatly between all states of Australia with respect to its application to fish. At this stage, it fails to even recognise the possibility that cephalopods or crustaceans could be sentient animals. This situation is mirrored around the world, with many exemptions to permit the continuation of the status quo with respect to recreational and commercial fishing. This situation needs to be reviewed in light of the growing body of evidence.

It is a great challenge to alter human behaviours which have their origins in the most primitive hunting traditions of the human species. However, the even application of welfare standards accepted for terrestrial species, should be afforded also to aquatic animals. The ethical and scientific evidence is increasingly supportive of improved welfare for aquatic animals requiring legislative adjustment, and effective compliance.

Acknowledgements

Dr Richmond Loh, has been closely involved with the genesis of this paper, and his contribution is gratefully acknowledged.

References

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